1. Field of the Invention
The present invention relates to a portable machine for cleaning planar surfaces, such as carpeted floors, upholstery, wall coverings and the like, as well as hard floor surfaces, and finds particular application in such machines where hot or cold cleaning liquids are sprayed onto the surface and are then removed by suction.
2. Description of the Prior Art
Cleaning systems that circulate and spray liquids are widely used for cleaning carpets, upholstery, fabric and wall coverings, as well as for hard surfaces such as tile and ceramics. Cleaning systems of this type which circulate and spray liquids often include a solution tank of liquid cleaning solution supported on a wheel mounted base or framework. The framework also supports a liquid pump for circulating the cleaning solution and one or more vacuum motors for recovering the solution and returning the used solution to a recovery tank. Many of these systems use a “cleaning head” which is part of a “cleaning wand” to spray liquid cleaning solution toward the surface being cleaned, for example, while the cleaning head is being pushed across the floor. In many such systems, the cleaning head is not integral with the base or framework, but rather is coupled to the solution tank through pliable hosing and the associated cleaning wand, which is thus is movable independently. A vacuum source creates a high velocity airstream through the wand head which draws the dispensed liquid from the surface being cleaned upwardly through the wand head and through the pliable hosing to the solution tank, thereby extracting soil, debris and other foreign matter to clean the surface.
A variety of devices of the above type are known in the relevant industries. For example, a commercially available line of carpet extractors of the above general type is sold as the “PFX1350 Series Extractors” by Powr-Flite®, a Tacony Company, 3101 Wichita Court, Fort Worth, Tex., 76140.
Alternatively, a surface cleaning apparatus can be self-contained, in the sense of providing a wheel supported housing that incorporates the necessary motors and contains the cleaning fluid, and further incorporates the cleaning tool head as a part of the same housing. In other words, the cleaning head is attached to the machine housing and rolls across the floor with the housing. A number of these type machines will also be familiar to those skilled in the relevant arts. For example, two such commercially available machines are sold as the “PFX3S and the PFX 900S Series Extractors” by Powr-Flite®, a Tacony Company, 3101 Wichita Court, Fort Worth, Tex., 76140.
The aforementioned devices, whether of the hose and wand variety, or of the self-contained housing variety, all utilize vacuum motors to draw up the dispensed cleaning solution from the surface being cleaned so that the used cleaning solution can be returned to a solution recovery tank. Depending upon the particular machine design, either one or two tanks may be used to dispense cleaning solution and then recover the dirty, used solution. In the case of the two tank machines, the majority of the dirty water and cleaning solution is recovered and then discarded. There are several disadvantages with such an arrangement, however. For example, where two tanks are used, they typically provide about twice the tank volume that is needed to hold the actual volume of treatment fluid. Another disadvantage is that the user has to carry the recovery tank when full to a disposal outlet, such as a sink, for disposal of the recovered solution and then refill the separate solution tank.
Because of these and other disadvantages, recent cleaning machines of this general type, e.g., carpet extractors, have been available in the marketplace which are designed to recycle the extracted cleaning solution for reuse. These machines utilize only a single, multi-purpose, dispensing and recovery “solution tank.” The result is the elimination of the additional “recovery tank”, as well as the need to dispose of the recovered cleaning solution in the tank several times during the cleaning operation. The one-tank system also reduces significantly the number of times the user has to stop and refill the solution tank.
A critical aspect of the design of the one-tank cleaning system of the type under consideration is the design of the solution tank itself, and of the filtration system used with the solution tank. The solution recovery tank is provided with one or more types of filter elements for straining dirt and debris from the cleaning solution. Obviously it is necessary to have an efficient filtration system in place to re-circulate and recycle the cleaning solution. The actual physical design of the solution tank itself can also impact upon the efficiency of the recovery and recycling operation.
A need exists, therefore, for a portable cleaning apparatus of the type which dispenses and then collects liquid cleaning solution from a surface being cleaned, which apparatus utilizes a single solution dispensing and recovery tank of optimum design.
A need also exists for such a cleaning apparatus which has incorporated therein an improved filtration system for filtering dirt and debris from the used cleaning solution prior to recirculating and reusing the cleaning solution on the surface being cleaned.
A need also exists for such a cleaning machine which is relatively simple in design and economical to manufacture.